Goldenseal (Hydrastis canadensis L.) Phytochemistry, Trade, and Habitat: Implications for Conservation and Forest Based Cultivation
Open Access
- Author:
- Zuiderveen, Grady
- Graduate Program:
- Forest Resources
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- May 30, 2019
- Committee Members:
- Michael Gregory Jacobson, Dissertation Advisor/Co-Advisor
Michael Gregory Jacobson, Committee Chair/Co-Chair
Margot Wilkinson Kaye, Committee Member
Douglas Alan Miller, Committee Member
Joshua D Lambert, Outside Member
Eric Paul Burkhart, Dissertation Advisor/Co-Advisor
Eric Paul Burkhart, Committee Chair/Co-Chair - Keywords:
- ethnobotany
forest farming
plant conservation
medicinal plants
agroforestry - Abstract:
- Goldenseal (Hydrastis canadensis L.) is a well-known medicinal, forest plant native to eastern North America. The roots and rhizomes of this species are used primarily as an antimicrobial and for the treatment of inflammation and intestinal ailments. Due to conservation concerns over the long-term viability of wild populations, the species has been listed in Appendix 2 of the Convention on International Trade of Endangered Species of Wild Fauna and Flora (CITES), an international trade treaty surrounding wild species. Concurrently, there is demand in the herbal industry for high quality, sustainably sourced goldenseal products. This study examined phytochemistry of wild harvested rhizomes and shoots; behaviors and perspectives surrounding goldenseal trade in the eastern United States; and habitat suitability and indicators in Pennsylvania. This interdisciplinary set of studies was undertaken to better understand and enhance wild conservation efforts, and to develop information that could be used to inform the adoption of cultivation, forest farming, and in situ wild stewardship. Phytochemistry studies were undertaken to investigate the occurrence of three isoquinoline alkaloids—berberine, hydrastine, and canadine—currently recognized as three major bioactive constituents in goldenseal. High performance liquid chromatography (HPLC) was used to look at the influence of development stage, time-of-day, habitat conditions, and drying temperature on variations in alkaloid concentrations in goldenseal rhizomes and shoots. Results indicate that harvest and post-harvest conditions and practices can greatly influence the total alkaloid concentration in the plant. Alkaloid concentration was found to peak in both plant shoots and in rhizomes at flowering stage and in the rhizomes in the dormancy stage. Hydrastine and canadine levels were found to be greatest in shoots in the afternoon. Habitat factors such as forest overstory canopy cover, plant density, and soil cation exchange capacity (CEC) were all found to influence alkaloid levels in goldenseal. Drying temperatures (26.7°C – 54.4°C) were found to influence canadine, which decreased as temperature increased. To better understand goldenseal trade behaviors and conservation perspectives, surveys were used to gather information around the management, trade, and conservation practices in Pennsylvania, and across the species natural range. Results indicate that trade is more significant and widespread in goldenseal’s core range (Ohio, Indiana, Kentucky, and West Virginia), and that this increased trade activity is also linked to perceived greater availability of goldenseal as a wild species and less concern by buyers over conservation. Further, there is a lack of state involvement in goldenseal trade tracking and management when compared with American ginseng, which is another CITES listed species. Results indicate that the state-to-state variation in harvest may require greater attention at the state, rather than federal, level to improve a regionally-focused approach to goldenseal conservation. Lastly, indicator species analysis and habitat suitability modeling were used to identify goldenseal habitat in Pennsylvania – a state at the northern edge of its range. The results identified bedrock type and the average winter temperature as important factors in determining suitable habitat. The most prevalent overstory tree associates with goldenseal populations were tulip-poplar (Liriodendron tulipifera) and sugar maple (Acer saccharum); common understory associates included spicebush (Lindera benzoin), Jack-in-the-pulpit (Arisaema triphyllum), and rattlesnake fern (Botrypus virginianus). Taken together, these results identified rich, mesic, woodland sites in the south and south-central part of the state as being suitable for goldenseal, and by prioritizing these areas for protection, management, and cultivation (i.e., forest farming), greater levels of conservation success could be achieved.